group *elset beam in other *elset and assign section, is it possible ?

[pls91]

Hello guys,
if i have a sets of element (beam) :
for example :

*Elset, elset=E1, instance=telaio-1, generate
 1,  8,  1
*Elset, elset=E2, instance=telaio-1, generate
  9,  16,   1

*Elset, elset=Ei ...

is it possible group E1,E2,...,E1 in different group :

*Elset, elset=Group1, instance=telaio-1
E1,E2
*Elset, elset=Group2, instance=telaio-1
E3,E4

and assign section ?

*Beam SECTION,SECTION=RECT, elset=Group1,ROTARY INERTIA=ISOTROPIC,material=concreteN
0.3,0.5
0,0,-1
*TRANSVERSE SHEAR
1e+11,1e+11,1
*Beam SECTION,SECTION=RECT, elset=Group2,ROTARY INERTIA=ISOTROPIC,material=concreteP
0.3,0.5
0,0,-1
*TRANSVERSE SHEAR
1e+11,1e+11,1

I tried so, but it does not work , you have any idea (any command different from *elset) ?
thanks in advance